In recent years, as a new type capacitor, a porous capacitor has been developed. The porous capacitor takes advantages of a tendency that a metal oxide formed on a surface of a metal such as aluminum forms a porous structure. The porous capacitor is configured by forming internal electrodes in pores and using the metal oxide as a dielectric.
Conductors are laminated on front and back surfaces of the dielectric. The electrodes formed in the pores are connected to either of the conductors on the front surface or the conductors on the back surface. The conductors not connected to the internal electrodes are insulated by a void or an insulating material. In this way, the electrodes formed in the pores function as counter electrodes facing each other via the dielectric.
For example, Japanese Patent No. 4493686 and Japanese Patent Application Laid-open No. 2009-76850 each disclose a porous capacitor having such a configuration. In Japanese Patent No. 4493686 and Japanese Patent Application Laid-open No. 2009-76850, the internal electrodes are formed in the porous, one end of the internal electrodes is connected to one of the conductors, and the other end is insulated from the other conductor.